async-gen-dstr-const-async-ary-ptrn-elision.js (2474B)
1 // |reftest| async 2 // This file was procedurally generated from the following sources: 3 // - src/dstr-binding-for-await/ary-ptrn-elision.case 4 // - src/dstr-binding-for-await/default/for-await-of-async-gen-const-async.template 5 /*--- 6 description: Elision advances iterator (for-await-of statement) 7 esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation 8 features: [generators, destructuring-binding, async-iteration] 9 flags: [generated, async] 10 info: | 11 IterationStatement : 12 for await ( ForDeclaration of AssignmentExpression ) Statement 13 14 [...] 15 2. Return ? ForIn/OfBodyEvaluation(ForDeclaration, Statement, keyResult, 16 lexicalBinding, labelSet, async). 17 18 13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation 19 20 [...] 21 4. Let destructuring be IsDestructuring of lhs. 22 [...] 23 6. Repeat 24 [...] 25 j. If destructuring is false, then 26 [...] 27 k. Else 28 i. If lhsKind is assignment, then 29 [...] 30 ii. Else if lhsKind is varBinding, then 31 [...] 32 iii. Else, 33 1. Assert: lhsKind is lexicalBinding. 34 2. Assert: lhs is a ForDeclaration. 35 3. Let status be the result of performing BindingInitialization 36 for lhs passing nextValue and iterationEnv as arguments. 37 [...] 38 39 13.3.3.6 Runtime Semantics: IteratorBindingInitialization 40 41 ArrayBindingPattern : [ Elision ] 42 43 1. Return the result of performing 44 IteratorDestructuringAssignmentEvaluation of Elision with iteratorRecord 45 as the argument. 46 47 12.14.5.3 Runtime Semantics: IteratorDestructuringAssignmentEvaluation 48 49 Elision : , 50 51 1. If iteratorRecord.[[done]] is false, then 52 a. Let next be IteratorStep(iteratorRecord.[[iterator]]). 53 b. If next is an abrupt completion, set iteratorRecord.[[done]] to true. 54 c. ReturnIfAbrupt(next). 55 d. If next is false, set iteratorRecord.[[done]] to true. 56 2. Return NormalCompletion(empty). 57 58 ---*/ 59 var first = 0; 60 var second = 0; 61 function* g() { 62 first += 1; 63 yield; 64 second += 1; 65 }; 66 67 var iterCount = 0; 68 var asyncIter = (async function*() { 69 yield* [g()]; 70 })(); 71 72 async function *fn() { 73 for await (const [,] of asyncIter) { 74 assert.sameValue(first, 1); 75 assert.sameValue(second, 0); 76 77 iterCount += 1; 78 } 79 } 80 81 fn().next() 82 .then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE) 83 .then($DONE, $DONE);